Thomas a



(No Model.) I

T. A. EDISON.

ELEUTRIG RAILWAY.

No. 339,278. Pateg edlg r. 6 ,1882

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u. Prrum, mmmr. Wuh'ngim ac Ururnn STATES PATENT OFFICE,

THOMAS A. EDISON, OF MENLO PARK, NE\V JERSEY, ASSIGNOR TO THE EDIFSO\ ELECTRIC LIGHT COMPANY, OF NEXV YORK, N. Y.

ELECTRIC RAILWAY.

'ZI EIIIFIC'ATION forming part Letters Patent No. 339,278, dated April 6, 1886.

Application filed August 14, 1882. Serial No. 69,266. (No model.)

To all whom it may concern:

Be it known that I, THOMAS A. EDISON, of Menlo Park, in the county of Middlesex and State of New Jersey, have invented a new and useful Improvement in ElectricRa-ilways, (Case No. 4685:) and I do hereby declare that the following is a full and exact description of the same, reference being had to the accompany ing drawings, and to the letters of reference marked thereon.

The object of the present invent-ion is to produce simple and efficient means for operating street-railroads by clectricity,wherein it is essential that there should be no obstruction 1 projecting above the surface of the pavement,

and that there should be two continuous metallic conductors for carrying the current to and from the motors of the various cars, having good electrical joints, and forming practically a continuous and integral metallic circuit, and wherein, further, it is desirable that such cond uctors should be concealed from sight and wholly protected from accidental external contact, and should, further, be independentofthe rails, so that such rails can be taken up and replaced orthc track otherwise repaired without breaking the circuit or becoming liable to form a short circuit.

The object is accomplished by providing each track of a street-railroad with a suitable tube or way, constructed preferably of metal, and located centrally between the rails. This tube rises only to the surface of the pavement, or slightly above the same, and has a continuone longitudinal slot in its top at the center thereof. Within the sunken tube are two continuous parallel conductors insulated from each other and forming rails, upon which travels a truck or small wheeled carriage having an arm projecting upwardly through the slot of the tube and attached to the car. Each car is provided with such a contact-truck. The two continuous conductors are connected with the dynamo or magneto electric machine or machines which supply the electrical energy for operating the motors mounted upon the cars. The wheels of each contact -truck have their rims insulated from their hubs, or they are otherwise insulated from each other. They conduct current from and to the conductingrails upon which they travel, and have contact brushes or springs bearing upon them and supported by the body of the truck, which brushes are connected with two conductors leading up through the arm attached to the car. From this arm the conductors run to the field and armature circuits of the electro-dynamic motor, such circuits being preferably independent multiple-arc circuits, and provided with suitable circuit controllers for making and breaking the circuits at will. In the armature circuit is located a current re versing device, as described in my application No. 61,955, by the manipulation of which the direction of the current through the coils of the armature can be reversed and the car made to travel forward or back ward at will without disturbing the commutator-brushes of the motor. An adjustable resistance may also be located in the field-circuit, or any other device be provided in the field or armature circuit or in the circuit common to both the field and armature coils, for changing the rate of speed as desired without disturbing the commutatorbrushcs of the motor, as described in my ap- 7 5 plication No. 68,645. The revolving armature of the motor is connected with one or more axles of the car by speed-reducing connections, so that the motor can run at high speed, and an endless belt, rope, chain, or other flexible 8o connection (one or more) is used as part of the connectionsin order to permit the car to move on its springs without aifecting the running of the motor, as described in my application No. 68,649. A. friction clutch is also preferably 8 5 used to throw the armature into and out of connection with the axle or axles, so that the car can be stopped without stopping the motor, as described in my application No. 68,649.

The foregoing will be better understood by 0 reference to the drawings, in which Figure 1 is a view, partly diagrammatic, of a street-railroad, and connections for working the same by means of electrical energy, the parts of the car illustrated being shown, for clearness, somewhat separated, and the slotted tube be ing in horizontal section; Fig. 2, a vertical section through the road-bed, with the car in end elevation, and Fig. 3, a vertical section, on a somewhat larger scale, of the continuous con- :00

ccaled conductors and support.

A A are the rails of one track of a streetrailroad, and B represents the pavement of the street. In the center of the track is the continous sunken tube 0, constructed preferably of metal, and having the continuous narrow slot at, extending along the center of its top. This tube rises to the surface only of the pavement, or slightly above, the lips of the slot projecting preferably above the body of the tube. The tube 0 may have pipes a, at intervals connected with the sewer, for carrying off the water.

D E are two continuous metallic conductors, which are supported within the tube 0, parallel with each other, by brackets b'of insulating material, secured to a longitudinal support, F, rising from the bottom of the tube 0. This support may be a line of T-beams, as shown.

' The conductors D E are connected with the conductors l 2, leading from the dynamo or magneto electric machine or machines G, which supply the-current.

His a truck having wheels 0 (I, which trave upon the conductors D E, and carry the current from and to such conductors. These wheels 0 d have their rims insulated from their hubs; or the wheel or wheels on one side of the truck are insulated in any other way from those on the other side, as described in my sulated conductors 3 4, running through the anal, and protected thereby from contact with the tube 0 at the sides of the slot at.

L is the electro-dynamic motor, mounted upon the car and connected with an axle or axles of the car through a flexible connection and a friction-clutch, as described in my applications before referred to. The armature and field coils of the motor are preferably in multiple-arc circuits from 3 4:, a suitable current-reverser, such as shown at M, being 1ocated in the armaturebircuit, and a device for varying the speed being also used, if desired, as described in my applications before referred to.

\Vhat I claim is 1. In an electrical railroad, the combination, with the parallel conductors inclosed within and concealed by a sunken slotted tube, of a car, a contact-truck attached to the car and having wheels traveling upon such parallel conductors, and connections from the wheels of the contact-truck to the motor on the car, substantially as set forth.

2. In an electrical railroad, the combination, with the parallel conductors inclosed within and concealed by a sunken slotted tube, of a contact-truck, an arm extending from such contact-truck to the car, and insulated conductors inclosed within such arm and protected thereby from contact with the sides of the slot, substantially as set forth.

3. In an electrical railroad, the combination, with the parallel conductors inclosed within and concealed by a sunken slotted tube, of a contact-truck riding upon such conduct 01's, and an arm from such truck attached to the car by a pivoted or loose joint and permitting of an independent movement of the car and contact-truck, substantially as set forth.

This specification signed and witnessed this 7th day of July, 1882.

THOMAS A. EDISON.

Witnesses:

RIOHD. N. DYER, EDWARD H. PYATI. 

